The objective of this project is a vaccine for dental caries. Dental caries can be provoked and transmitted by infection with mutans streptococci. Preclinical and clinical trials have demonstrated that caries incidence declines when mutans streptococcal challenge is modified. Immunization with antigens derived from mutans streptococci, e.g., glucosyltransferase (GTF), reduces the rate of colonization. Once colonization has taken hold in an adult population, eradication via immunization is unlikely; however, most children do not become colonized until after 18 months of age. A vaccine formulation which targets early childhood immunization is reasonable. In preliminary studies in rodents, we have shown that a GTF microparticulate, formulated by incorporation into a poly(lactic-co- glycolic) acid (PLGA) excipient, was capable of inducing mucosal immune responses. Modifications in the delivery system formulation methods are now proposed to increase the efficiency of immune induction via GTF. We will expand upon the PLGA technology used in the preliminary GTF studies and increase particle uptake by incorporation of a bioadhesive into the GTF/PLGA particulate. The objective of the proposed Phase I studies is to demonstrate that these novel bioadhesive GTF/PLGA formulations will elicit a strong and sustained immune response, the goal of the overall SBIR program being the development of a dental caries vaccine for childhood immunization. PROPOSED COMMERCIAL APPLICATION: Microencapsulation of vaccines for oral delivery present a significant advancement in vaccine technology. Oral immunization is a more convenient, safer, and perhaps, more efficient replacement of needle-based vaccine delivery. Many vaccine manufacturers would be a potential commercial market for development/utilization of this technology for not only its application to dental caries, but also to mucosal infections.